The present disclosure relates to a the casting mold evacuation valve assembly.
To permit reliably preventing air or gas pockets in the finished casting, the mold or its cavities are automatically evacuated during casting. To do this, not only the air existing in the cavities of the casting mass and the mold must be able to escape, but in addition it must also be assured that also the gases emerging from the casting mass can escape.
The problematics in evacuating die casting molds involve preventing under all circumstances that the molten casting mass is able to escape into the environment. To prevent this happening, valve assemblies are employed which are provided with an evacuation duct connected to the mold cavity of the die casting mold, an evacuation valve arranged in the evacuation duct and an actuator for closing the evacuation valve. Valve assemblies are known designed for pilot control and by the casting material. The latter feature an actuator comprising a force transducer actuated by the casting material and a member for transferring the force of the closing member from the force transducer to the evacuation valve. One such valve assembly is known from EP 0 612 573 A2. Although such a valve assembly is very reliable in operation in thus achieving a very fast closing response, being able to adapt the valve assembly more specifically to the requirements at locations subject to high stress and strain remains desirable.
The object of the invention is to provide a valve assembly for evacuating die casting molds which although hard-wearing is nevertheless still relatively cost-effective in production.